During the past ten years,
methanesulphonic acid has largely replaced fluoroboric acid as the electrolyte of choice for the
electrodeposition of tin and tin-lead solder on electronic devices. Certain other electrochemical processes involving lead, most notably the electrorefining of lead by the Bett's process, are currently carried out in fluorosilicic acid based electrolytes but those based on
methanesulphonic acid (MSA) are being actively investigated as environmentally superior alternatives to the currently used systems. Also, a number of commercial strip steel tin-plating operations have recently converted to
Methanesulphonic acid based tin-plating electrolytes. There are also developing markets for methanesulphonic acid in silver, nickel, copper, cadmium and zinc electroplating. This paper reviews the chemical and physical properties of methanesulphonic acid and its current applications in the field of metal finishing and also its superiority over other electrolytes especially with respect to environmental pollution.